It is not a process argument, but rather a matter of constitutional preservation.
Twenty-one State Attorneys’ General submit a brief to the Senate (full pdf below) in support of complete rejection for the House articles of impeachment.
…”If not expressly repudiated by the Senate, the theories animating both Articles will set a precedent that is entirely contrary to the Framers’ design and ruinous to the most important governmental structure protections contained in our Constitution: the separation of powers”…
South Carolina Attorney General Alan Wilson along with twenty additional State AG’s, submit a 14-page briefing (download here) to the United States Senate warning of the danger of not rejecting a purely partisan political impeachment effort. The Attorneys’ General note the current impeachment proceedings are “fundamentally flawed as a matter of constitutional law.” Their concerns are echo points starting to be realized by Senators.
During a press conference in front of the U.S. Capitol Wednesday, South Carolina AG Alan Wilson said the group was urging the Senate to “reject these articles” as a matter of constitutional law. WATCH:
Here’s the Brief:
“Because the legal theories underlying both Articles I and II are legally flawed and factually insufficient, as well as inherently destructive of separation of powers, the Senate should explicitly reject them to protect both the institution of the Presidency and the Constitution.
A close examination of the legal theories and stipulations of fact accompanying Articles I and II reveal their fatal flaws.2 It is important to note that the focus of this legal analysis will be on the stipulations of fact relied upon by the House at the time of the impeachment vote because this is the precedent upon which all future impeachment proceedings will rely.”
It is a well written brief and exactly on point.